top of page

green crystal

Process blog for my pandemic project.

concept and model

I was lucky to get an amazing character model from the awesome Tiffany Ribera-McKay, inspired by a drawing by Fukari on deviantart. 


My current plan:

  • Render with RenderMan for Maya

  • Texture with Substance Painter

  • Groom with XGen

  • Maybe use Houdini?

inspiration and reference


Eiti Sato on ArtStation

My Post.png

I've included the two characters on the left because I feel they hit the style that I'm aiming for with my own character. I like the quality of the skin (it's "tactile") without becoming uncanny. 

Andrey Lizunov on ArtStation



I started with the texturing and shading of the crystal on her necklace. I'm using a layered shader in Renderman, mixing my main crystal shader with a glass shader tinted yellow-green. I made the textures in Substance Painter. 

I decided to diverge from the art by making it transparent at the top and rougher/more opaque at the bottom. I am not married to this look and might go back to the way the art feels a little more. 


Added a dark grey shader for the "string" and a gold shader for the metal. 


I'm putting the crystal on hold and working on the skin displacement for a bit in Substance Painter. I was able to use some of the tileable maps/scans that come for free in Substance Painter for most of the face. I would like to use Mari, but my computer can't handle it.

  • upper lip looks weird

  • bottom of nose is too bumpy?

  • need displacement under eyes

  • top of nose doesn't blend well into forehead


In the images above, I was fighting my lighting and seeing my skin blow out (there is no spec on that render). I adjusted my key/fill, but I accept that some areas may blow out because I am viewing in sRGB instead of an ACES LUT or a similar view transform.

I was lucky to get some notes from the other Blue Sky character materials artists on the image to the left. 

  • too bumpy overall - let subsurface soften it a bit to maintain roughness variation 

  • need to be more porous in some areas (bumping in and out)

  • repeating capillary shape in color map

  • freckles don't read clearly enough


I did what I could to hit the notes from my teammates about the skin. I might revisit that and the crystal later but wanted to move ahead to the eyeballs. 

My "style references" don't have much detail in the whites of the eyes/sclera, so I am not adding any veins or diffuse & bump texture there. I used the model and painted over the iris color map that came with Tom Newbury's gumroad eyeball tutorial linked above. 



Tiffany made some amazing hair tubes for this model, which I am using in XGen for my groom.

XGen requires tubes to be open on both ends, which I wanted to do using the carve sop in Houdini. Unfortunately their point order is scrambled, which means I'd need to rebuild the tubes in order to carve them. So I'm manually deleting faces from the tubes in Maya to open them up. 


Now that I have access to the Learning license Houdini, I can render with Renderman for Houdini. So once I make all my guides in Maya, I will move over to Houdini and recreate all my Renderman shaders...


I was having a problem with generating guides from my tube geometry, in that the tubes seemed ok but the hairs tried to connect back to the scalp at the ends. One of my awesome Fur coworkers at Blue Sky told me I might need to flip my UVs on my tubes. So I planar projected all my tubes and flipped the UVs in the V direction, and the hairs generated from the tube like I expected.


hair attempt 2

After a few months hiatus from this project, I am back and trying to redo the groom in Maya. I tried to do the groom 100% in Houdini, but I decided to start in XGen.

I tried to convert my legacy xgen groom to interactive xgen, so I can use the uv and id primvars in Renderman. The conversion wasn't very successful because I had difficulties controlling the clumping. I wanted to use "clump points" or clump guides the way I did in the legacy XGen or the way you could do it in Houdini.


Ultimately, I decided it would be easier to complete this groom in Houdini using the guides I made in legacy XGen.

I'm currently not happy with the "final" result because I think the clumps don't look natural enough. I struggled to find a balance between the art-directed shapes and making a natural-looking hair texture. Many of the clumps are also intersecting, which I find distracting.


eyelashes & eyebrows

I chose to go pretty thick with the eyelashes and eyebrows and not very natural (especially with the eyelashes).

For the eyelashes, I wanted the bold definition of the upper lashes from the original concept, without feeling too "spidery" or sparse.


hair coloring


This was fun for me. I love unnatural hair colors (of course my own hair in real life is pink ) so I was excited.

I tried this at first with a root-to-tip ramp (left image), but it was too obviously a root-to-tip ramp and not similar to the way a real balayage would be painted. So I made a normalized length signal and used that for the ramp instead (right image).


almost finished

At this point, I had gone back and forth between using RenderMan in Solaris, lighting/lookdeving and rendering everything in the LOPs context. But for these renders, I decided to go with RfH and render everything in the /out context, doing the materials in /mat.


I did the leaves and flowers textures in Substance Painter.


At this point, I kind of thought I was done, but I wasn't 100% happy with it, yet.

gC_13_comp (2021_01_09 00_47_30 UTC).png
gC_14_comp (2021_01_09 00_47_30 UTC).png
gC_13_ao (2021_01_09 00_47_30 UTC).png

actually finished

In these renders, I went back into XGen and added more guides around the head (the back and sides were a bit too sparse).

I had a lot of trouble with the hair intersecting with the leaves. I tried to make sure all the guides were under the leaf crown, but once the hair is generated, there was a lot of volume, and some of the hair is sitting on top of the leaves. It's not perfect.

I also got some great feedback from a teammate at Blue Sky to reduce the bump/displacement detail on the nose and cheeks, and reduce the redness and shininess of the nose. I implemented those notes, and I think she looks a lot better now.

I learned a lot from this project, and it's the longest amount of time I've ever spent on one thing.
I worked on it on-and-off for 9 months. Now it's time to move on to bigger and better things!

bottom of page